SM electrics are known to have issues at the bottom of the hole. And I have to say that some of the numbers I've seen for electric augers (SM and ION) in terms of inches of ice they'll do on a single charge make me raise my eyebrows.
Still, sounds like OP should return the one they got and try a new one. Any 40V electric should light up any gas auger in terms of speed. There is no comparison in torque. Same reason a four door Tesla can annihilate any ICE supercar in a race.